A widely followed Apple analyst, known for accuracy, cut his sales estimates for the iPhone XR Friday, exacerbating sweeping concerns across the investment community that the tech giant is experiencing a slowdown in its iPhone cycle.

TF International Securities analyst Ming-Chi Kuo wrote in a report to clients that he was cutting iPhone shipment estimates for the first quarter of 2019, again, due in part to lower-than-expected iPhone XR demand.

He said that the “increase in orders of legacy iPhone models cannot offset the decline of XR and XS series shipments because of the low season impact.”

More granularly, Kuo wrote that he was reducing his shipment estimates for the XR in the first quarter of next year to between 15 million and 20 million units, from his previous forecast of 20 million to 25 million units. Total 2019 iPhone shipments are likely to come in between 188 million and 194 million units, representing a decline of 5- to 10% year-over-year, he said.

The report, which sent Apple shares falling 2% Friday, said the decline in full-year shipments for 2019 would come as a result of newer models’ lower-than-forecast replacement demand and “low season impacts” for the first half of the year. Painting a grimmer picture, in the latter half of the year, “new iPhone models may not grow” due to “no major upgrades.”

Still, the analyst said the company’s iPhone revenue could rise in 2019 due to the increase in the smartphones’ average selling price, but that a decline in shipments remains unfavorable for the broader supply chain. Risks Apple faces, Kuo said, include a delay in new product shipments and lower-than-expected demand.

The report comes as other market watchers and investors fear the next year could be a grim one for the tech giant, prompting analysts to temper their recommendations on the stock and suppliers to take down their own forecasts.

Apple is likely to suffer a revenue loss for its current iPhone cycle for just the second time in the smartphone’s exi stance, according to a UBS estimate. The culprit? Weak demand for the iPhone XR, according to analyst Timothy Arcuri.